87 years. Lincoln used references to time and America’s history in many of his speeches and documents, most famously in his Gettysburg Address, “Four score and seven years ago our fathers brought forth, upon this continent, a new nation, conceived in liberty…”.

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87 years. Lincoln used references to time and America’s history in many of his speeches and documents, most famously in his Gettysburg Address, “Four score and seven years ago our fathers brought forth, upon this continent, a new nation, conceived in liberty…”.